The objective of the proposed investigation is to gain an understanding of the mechanism by which jellyfish toxins exert their observed clinical symptoms. To this end, toxin from the jellyfish Stomolophus meleagris has been selected as a model toxin for intensive biochemical, physiological and pharmacological studies. Since ongoing investigations in this laboratory have shown that this toxin possesses a number of substances which interfere with membranes and transport processes across membranes, emphasis throughout this investigation will be on the isolation, characterization and cause-effect relationships of these substances in the toxin. Specifically, we propose to isolate, chemically characterize, establish the role each plays in the physiological and pharmacological symptoms of toxin injected animals, and establish the sub-cellular mechanism of action of (1) those components of the toxin which might result in altered Na ion - K ion transport across membranes; (2) those components of the toxin which result in altered Ca ion transport across membranes and/or effect the binding and/or uptake of Ca ion by mitochondria and/or sarcoplasmic reticulum; (3) those components of the toxin which result in histamine release; (4) those components of the toxin which result in hemolysis of erythrocytes and (5) those non-protein, low molecular weight components of the toxin. In addition, a series of studies will be undertaken to establish the synergistic effects produced at both the sub-cellular and isolated organ level, as well as in test animals of these isolated components.